ShopUpdate before creating or restoring a wallet.
Mk4 uses the current Mk4/Mk5 firmware family. Check the current security status, install and verify the recommended release, and follow the migration guide for any seed created on affected firmware. Installing firmware does not repair an existing affected seed.
Support for Mk4 owners
Current firmware
Download the current standard Mk4/Mk5 release and verify its signed hashes before installation.
Upgrade instructions
Follow the MicroSD or Virtual Disk procedure and confirm the installed version on the device.
Mk4 hardware reference
Review the Mk4 hardware, connector, memory, NFC, secure-element, and virtual-disk details.
Troubleshooting
Work through firmware, power, MicroSD, USB, signing, and wallet-connection problems.
What remains current
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Shared firmware support
Mk4 and Mk5 use the same standard firmware track. Release notes identify any hardware-specific exceptions.
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Current seed-generation controls
Bring Your Own Entropy remains required for standard new seeds. On Mk4/Mk5 5.6.2 or later,
View TRNG Wordssupports offline verification of dice-roll or coin-flip mixing; the verification tool does not support key mashing. -
Existing workflows
Mk4 continues to support MicroSD, NFC, USB and Virtual Disk PSBT workflows, dual secure elements, encrypted backups, Trick PINs, SeedXOR, and BIP-85.
Buying a new COLDCARD?
Mk5 replaces Mk4 in the compact numeric-keypad form factor. It retains the familiar workflow with a larger Gorilla Glass screen, improved keyboard, and current hardware.